Level sensor and heating unit



FIG. 1 is a front perspective view of a level sensor and heating unit showing my new design;

FIG. 2 is a left side elevation view thereof;

FIG. 3 is a top plan view thereof; and,

FIG. 4 is a front elevation view.

In the drawings, the broken lines depict unclaimed subject matter only and form no part of the claimed design. 

I claim the ornamental design for level sensor and heating unit, as shown and described. 